Journal of Forest Science, 2009 (vol. 55), issue 9
Comparison of deposition fluxes on the open area and in mountain spruce stands of different density
I. Marková, I. Drápelová, S. Truparová
J. For. Sci., 2009, 55(9):395-402 | DOI: 10.17221/37/2009-JFS 
To better understand the chemical transformation of rainfall after the passage through the canopies it is necessary to study throughfall deposition fluxes within forest stands. The comparison of bulk deposition fluxes of Ca, Mg, K, S-SO4, N-NO3 and N-NH4 in mountain spruce stands of different stand density and bulk deposition fluxes on the open area was made at the study site Bílý Kříľ (Moravian-Silesian Beskids Mts., Czech Republic) during the period of 1999-2006. A linear relationship between the amount of rainfall on the open area and the amount of throughfall in the spruce stand was found. Throughfall deposition...
A study on the variation of morphological characteristics of silver fir (Abies alba Mill.) seeds and their internal structure determined by X-ray radiography in the Beskid S±decki and Beskid Niski mountain ranges of the Carpathians (southern Poland)
K. Skrzyszewska, J. Chłanda
J. For. Sci., 2009, 55(9):403-414 | DOI: 10.17221/48/2008-JFS
The variation of the morphological characteristics and internal structure of silver fir (Abies alba Mill.) seeds from 4 stands growing at the altitude of 625-750 m in the Beskid S±decki and Beskid Niski mountain ranges of the Carpathians in southern Poland was estimated. Seeds were collected in the second half of September 2004. The weight of 1,000 air-dry seeds was determined and their viability was estimated with the use of X-ray radiography. The length and width of the embryo, endosperm and embryo cavity were measured on X-ray photographs. The morphological seed characteristics, i.e. length, width, volume, surface area, and wing colour (light-brown,...
Variability of spruce (Picea abies [L.] Karst.) compression strength with present reaction wood
V. Gryc, H. Vavrčík
J. For. Sci., 2009, 55(9):415-422 | DOI: 10.17221/13/2009-JFS
The aim of research was to find out the variability of spruce (Picea abies [L.]) Karst.) wood compression strength limits in the direction parallel to grain. The wood strength was examined using samples from a tree with present reaction (compression) wood. The strength was found out for individual stem zones (CW, OW, SWL and SWR). The zone with present compression wood (CW) demonstrated slightly higher values of wood strength limits. The differences in the limits of compression strength parallel to grain in individual zones were not statistically significant. All the data acquired by measuring were used to create 3D models for each zone. The...
Comparison of three methods to determine optimal road spacing for forwarder-type logging operations
M. R. Ghaffarian, K. Stampfer, J. Sessions
J. For. Sci., 2009, 55(9):423-431 | DOI: 10.17221/79/2008-JFS
Optimum road spacing (ORS) of forwarding operation in Styria in Southern Austria is studied in this paper. In a harvesting operation it is important to compute the ORS to minimize the total cost of harvesting and roading. The aim of this study was a comparison of different methods to study ORS. Data from 82 cycles were used to develop two models for predicting the cycle time using statistical analysis of a time study data base. The ORS was computed by three methods including Matthews' formula (1942), Sundberg's method (1976), and the two statistical models for predicting the cycle time. The results gave the ORS for one-way forwarding using Matthew's...
Multiaged silviculture in North America
K. L. O'Hara
J. For. Sci., 2009, 55(9):432-436 | DOI: 10.17221/4/2009-JFS
Multiaged silviculture is highly variable across North America but a commonality is the ties to the negative exponential diameter distribution to guide stocking control. These methods have evolved in several regions to include alternative stand structures and new stocking control tools are being developed. A trend in these new developments is integrating disturbance regimes and their effects on stand structure. The result, in some cases, is a movement towards longer cutting cycles and more flexible guidelines for stand structure.